[dsavitsk]

Short answer is, I am not sure. The slightly longer answer is that the HPDAC has 3 grounds. The real ground, which is your computer's ground, acts as the ground for the DAC portion and the negative rail for the amp section. Ground #2 is the amp section's virtual ground. Ground #3 is the output ground.

The metal on the EVJ is isolated as is the USB jack. The only part that might not be is the metal ring on the recommended output jack. Since most people are using the case with the plastic end panels, this is not an issue at all. If you are using the case with the metal end panel, it should still not be an issue unless something else is touching the case. So, basically, the case is probably isolated, but at worst could be connected to the buffered ground.

As for the computer issue, it is possible for a shock to cause a problem, but this would likely be an issue with the computer itself and how it is grounded. But, the computer's ground is connected directly to the hpdac, so it is worth investigating.

 

[Magsy]

I've had the reboot thing too with Guzzler's USB Dac, infact by shorting USB power you can reboot at will

I have had the machine reboot once when I touched the DAC and a metal radiator, so that sounds similar to yours...

I didn't actually do anything to fix it other than case it properly - it does not come into contact with the chassis at all and all connectors are isolated.

 

[civilmonkey]

Quote:

Originally Posted by dsavitsk The metal on the EVJ is isolated as is the USB jack. The only part that might not be is the metal ring on the recommended output jack. Since most people are using the case with the plastic end panels, this is not an issue at all. If you are using the case with the metal end panel, it should still not be an issue unless something else is touching the case. So, basically, the case is probably isolated, but at worst could be connected to the buffered ground.

I used metal case / ends. Two things. I found that I hadn't trimed excess leads from the underside of the board enough and they were contacting the case causing problems. I also ended up isolating the USB jack and POT, but not the output jack. Although I just read the jack and pot are already isolated... I could have sworn my multimeter told me different.

 

[dsavitsk]

Quote:

Originally Posted by civilmonkey /img/forum/go_quote.gif Although I just read the jack and pot are already isolated... I could have sworn my multimeter told me different.

You might trust your multimeter over me. Mine just got through telling me that a 160V supply was 450V. Mine did seem to be isolated, but it is probably better to be safe and consider them grounded.

 

[jdimitri]

Sorry to go OT, but is the hpdac asio compatible?
Mine should be here soon, i'm just wondering what i should do to get asio etc working in foobar
Thanks!

 

[MisterX]

ASIO4all is all it takes.

 

[nleahcim]

I'm a little late here - but are there still PCBs available?

 

[psilosome]

Quote:

Originally Posted by nleahcim /img/forum/go_quote.gif I'm a little late here - but are there still PCBs available?

It looks that way

 

[nichone]

Hi

I put together a HPDAC with standard parts and it worked for two
songs. I got up and swapped headphones and got no sound.
After much examination, resoldering, replacing the USB socket, DMM testing,
and retesting, I can get it to work - or not. Sometimes still I get nothing;
LED lights but no hiss or sound. More commonly now I get an tincan sound
where the lows and highs are missing. But if I flex the PCB in the correct corner I get full sound. I have to put my right hand thumb below the end
of the board and my fingers presssing down on the USB socket housing and
cable connector.
I initailly thought the USB to PCB ground connection was bad or
shorted. I had found the "fix" by bending down the USB connection.
A resistance check showed a poor connection ( end of USB cable to PCB
bottom ). Changing cables and computers did nothing. I played with the
socket until I just replaced it. Initially I also had low output voltage at the
5 volt regulator which was affected by the bending PCB. Now fixed,
The voltages are good at the outputs now - whether the sound is tincan or normal.
I have to be closing a gap or breaking a short, but where ? Any ideas ?

Thanks in advance. John.

 

[Clutz]

I would go back and try re-flowing each of the solder joints - possibly with some liquid fluid, and then clean the board up really well using denatured alcohol. It sounds to me like you have a cold solder joint somewhere.

 

[nichone]

Thanks. You were right. I was worried about component failure.
After posting I again retested every connection - device lead to distal
device - all checked out OK. Then while rechecking the voltage outputs
I flexed the headphone jack end ever so slightly and got the good sound.
I redid every connection on that end of the board (again) and now it works.
So I had the wrong side and some invisible poor joint - probably at the
opamp(s). I hope this helps someone else.

 

[Magsy]

4 o'clock in the morning but I am done, couple of issues, mainly offset from the AD 8058 I've fitted, fine until high volume then 50mv+ upto nearly 300mv at full.
Also it only seems to work in my apple usb keyboard (Intel PC), not direct in my usb ports - probably machine issue, I had similar thing with Guzzler usb dac.

But....It sounds totally amazing. I was ready to be disappointed compared to either my standalone DAC or the 0404 but it really holds its own in a quick test. It has loads of volume with my HD580, which is something I was worried about because I like it loud

No noise, even on my main rig which has every pci slot filled.

Good job, I'm very happy

 

[Polaris111688]

Congrats, dude. Got pics?

 

[Magsy]

Needs to be cleaned up, the leads are temp just to check it works!

All out boutique parts assault, BG N's all round and Riken resistors, AN8005/8 reg's (when they arrive)
Forgot the Rikens for R1/R2, to be replaced next time I order!

Not worried about the cost, I did it because I could!

 

[Magsy]

Seem to have a little problem with my REG101. I checked the output and it was the same as the input, 4.75v. I replaced it with a fresh one and it is the same.

What could be causing the regulator to seemingly not regulate? I've reflowed all the joints but they look ok, all of the 3.3v pins on the pcm2707 read 4.75v

When using the REG101 I was supposed to populate everything right? Not leave anything out?

Even with no Reg101, I read 4.75v across C9 and C11. I have checked and checked for shorts at the 2707 but I am almost positive there are none.

Edit: I even read 4.75v across C8 with no Reg101 in place, the DAC also works without Reg101 installed!?! :|